This invention relates to novel N-hydroxyurea and hydroxamic acid derivatives. The compounds of the present invention inhibit the action of the enzyme lipoxygenase and are useful in the treatment or alleviation of inflammatory diseases, allergy and cardiovascular diseases in mammals, especially human subjects. This invention also relates to pharmaceutical compositions comprising such compounds.
Arachidonic acid is known to be the biological precursor of several groups of biologically active endogenous metabolites. The first step in the metabolism of arachidonic acid is its release from membrane phospholipids, via the action of phospholipase A2. Arachidonic acid is then metabolized either by cyclooxygenase to produce prostaglandins including prostacyclin, and thromboxanes or by lipoxygenase to generate hydroperoxy fatty acids which may be further converted to the leukotrienes. The leukotrienes are extremely potent substances which elicit a wide variety of biological responses, often in the nanomolar to picomolar concentration range. The peptidoleukotrienes (LTC.sub.4, LTD.sub.4, LTE.sub.4) are important bronchoconstrictors and vasoconstrictors, and also cause plasma extravasation by increasing capillary permeability. LTB.sub.4 is a potent chemotactic agent, enhancing the influx of leukocytes and inducing their subsequent degranulation at the site of inflammation. A pathophysiological role for leukotrienes has been implicated in a number of human disease states including asthma, rheumatoid arthritis, gout, psoriasis, adult respiratory distress syndrome, inflammatory bowel diseases (e.g. Crohn's disease), endotoxin shock, and ischemia-induced myocardial injury. Any agent that inhibits the action of lipoxygenases is expected to be of considerable therapeutic value for the treatment of acute and chronic inflammatory conditions.
Among the compounds of similar structure to the object compounds of the present invention are those disclosed in EP 459748 A2 and WO 89/04299.